1. Field of the Invention
The present invention relates to an image recording apparatus applicable to printers, copying machines, electronic typewriters, facsimile equipment, and the like.
2. Related Background Art
In recent years, various kinds of information processing systems have been developed in conjunction with rapid progress made in the information industry, and recording methods and apparatus suitable for various information processing systems have also been developed and adopted. Among such recording methods, the thermal transfer recording method has recently been used widely, since the associated apparatus may be light in weight, compact and noise-free as well as excelling in terms of operational features and maintenance capabilities.
This heat transfer recording method is generally effected as follows A heat transfer medium is used in which a thermal transfer ink with a coloring agent dispersed in a heat melting binder is applied to a sheet-like substrate, and this thermal transfer medium is superposed on a recording medium in such a manner that a thermal transfer ink layer will contact the recording medium. By supplying heat from the side of the thermal transfer medium's substrate by means of a thermal head to transfer the melted ink layer to the recording medium, a transferred ink image corresponding to the configuration of the heat supplied is formed on the recording medium. In accordance with this method, plain paper can be used as the recording medium.
However, conventional thermal transfer recording methods are not free from problems. In other words, with conventional thermal transfer recording methods, the transfer recording performance, i.e., the printing quality, is substantially affected by the smoothness of the surface of the recording medium. In the case of a recording medium with a low degree of smoothness, there is a possibility of this resulting in a decline in the quality of images recorded.
In addition, if a multi-color image is to be obtained using a conventional thermal transfer recording apparatus, it is necessary to provide a plurality of thermal heads or provide the transfer recording medium or the recording medium with complicated functions such as reverse feeding and stopping. Thus, there are problems in that the overall apparatus becomes large in size and complex, and that the recording speed declines.
Therefore, the present applicant invented image recording methods and transfer recording media which allow high-quality images to be recorded on a recording medium having a low degree of surface smoothness by overcoming the aforementioned problems of the prior art. In addition, the present applicant invented image recording methods and transfer recording media which allow multi-color images to be obtained without needing to have the recording medium perform complicated functions. The present applicant filed patent applications in Japan for these inventions as Japanese Patent Application Nos. 120080/1985 (filed on June 3, 1985), 120081/1985 (filed on June 3, 1985), 131411/1985 (filed on June 17, 1985), 134831/1985 (filed on June 20, 1985), 150597/1985 (filed on June 7, 1985), 199926/1985 (filed on Sep. 10, 1985), and 250884/1985 (filed on Nov. 11, 1985). Furthermore, on the basis of the priority rights afforded by these Japanese applications, the present applicant filed an application in the United States (U.S. Ser. No. 869,689, filed on June 2, 1985) and a European application (Application No. 86107540.6, filed on June 3, 1986).
The present invention which will be described below is a further development of the aforementioned inventions for which the present applicant filed the Japanese applications, the U.S. application, and the European application. The present invention can be applied, as necessary, to the image recording methods and transfer recording media described in the specifications of the aforementioned applications.